Used to select all modules including boxes, set when both `full` and `boxes` are true in the constructor, pulling down `full_selection`.
Add `Selection::selects_all()` method as short hand for `full_selection || complete_selection`.
Update selection operations to account for complete selections.
Add static methods to `Selection` for creating a new empty/full/complete selection to make it clearer to users when doing so.
Use said static methods to replace most instances of the `Selection` constructor.
Update `Selection::optimize` to use
New methods on Design to push/pop selection instead of accessing the selection stack directly. Includes methods for pushing a full/complete/empty selection.
Also helper methods on modules to check `is_selected` and `is_selected_whole`.
Now uses two enums, one to control whether or not to include partially selected
modules (and what to do if they are encountered), and one to control whether or
not to include boxed modules (and what to do if they are encountered).
Mark Design::selected{modules, whole_modules}() deprecated and make them
provide warnings on boxes. There are a lot of places that use them and I can't
always tell which ones support boxed modules and which don't.
The `Design::selected_*()` methods no longer unconditionally skip boxed modules. Instead, selections are now box and design aware.
The selection constructor now optionally takes a design pointer, and has a new `selects_boxes` flag. If the selection has an assigned design, then `Selection::selected_*()` will only return true for boxed modules if the selects_boxes flag is set. A warning is raised if a selection is checked and no design is set. Selections can change design via the `Selection::optimize()` method.
Most places that iterate over `Design::modules()` and check `Selection::selected_module()` should instead use `Design::selected_modules()`.
Since boxed modules should only ever be selected explicitly, and `full_selection` (now) refers to all non-boxed modules, `Selection::optimize()` will clear the `full_selection` flag if the `selects_boxes` flag is enabled, and instead explicitly selects all modules (including boxed modules). This also means that `full_selection` will only get automatically applied to a design without any boxed modules.
These changes necessitated a number of changes to `select.cc` in order to support this functionality when operating on selections, in particular when combining selections (e.g. by union or difference).
To minimize redundancy, a number of places that previously iterated over `design->modules()` now push the current selection to the design, use `design->selected_modules()`, and then pop the selection when done.
Introduce `RTLIL::NamedObject`, to allow for iterating over all members of a module with a single iterator instead of needing to iterate over wires, cells, memories, and processes separately.
Also implement `Module::selected_{memories, processes, members}()` to match wires and cells methods. The `selected_members()` method combines each of the other `selected_*()` methods into a single list.
Drop the parts that are being dropped.
Move the things that are being moved.
Also move the verilog stuff out of README and into the docs.
GettingStarted is less cut and dry, so hold off on that one.
`Const::size()` returns int, so change iterators that use it to `auto` instead of `size_t`.
For cases where size is being explicitly cast to `int`, use the wrapper that we already have instead: `Yosys::GetSize()`.
There's a mismatch between what `kernel/mem.cc` emits for memories
with no read ports and what the internal RTLIL check expects.
The point of dispute it whether some of the parameters relating to read
ports have a zero-width value in this case. The `mem.cc` code says no,
the internal checker says yes.
Surveying the other `$mem_v2` parameters, and internal cell parameters
in general, I am inclined to side with the `mem.cc` code.
This breaks RTLIL compatibility but for an obscure edge case.
This is already supported by `SigSpec` and since both `SigChunk` and
`SigSpec` implement `extract` which is the multi-bit variant of this,
there is no good reason for `SigChunk` to not support
`SigBit operator[](int offset)`.
Only the `B` input (the shift amount) can be marked as signed on a
`$shiftx` cell. Adapt the helper accordingly and prevent it from
creating invalid RTLIL when called with `is_signed` set. Previously
it would mark both `A` and `B` as signed.
Previously `extract` on a `SigSpec` would always unpack it. Since a
significant amount of `SigSpec`s have one or few chunks, it's worth
having a dedicated implementation.
This is especially true, since the RTLIL frontend calls into this for
every `wire [lhs:rhs]` slice, making this `extract` take up 40% when
profiling `read_rtlil` with one of the largest coarse grained RTLIL
designs I had on hand.
With this change the `read_rtlil` profile looks like I would expect it
to look like, but I noticed that a lot of the other core RTLIL methods
also are a bit too eager with unpacking or implementing
`SigChunk`/`Const` overloads that just convert to a single chunk
`SigSpec` and forward to the implementation for that, when a direct
implementation would avoid temporary std::vector allocations. While not
relevant for `read_rtlil`, to me it looks like there might be a few easy
overall performance gains to be had by addressing this more generally.
This PR speeds up by roughly 17% across a wide spectrum of designs
tested at Google. Particularly for the mux generation pass.
Co-authored-by: Rasmus Larsen <rmlarsen@google.com>
Signed-off-by: Ethan Mahintorabi <ethanmoon@google.com>
This does not correctly handle an `$overwrite_tag` on a module output,
but since we currently require the user to flatten the design for
cross-module dft, this cannot be observed from within the design, only
by manually inspecting the signals in the design.
The guard is optimised out on some compilers under certain conditions (eg: LTO on GCC) as constant under C++ lifetime rules.
This is because the guard type's member is invalid to access (UB) after the type has been destroyed, resulting in
`destruct_guard.ok` being unable to be `false` according to the optimiser, based on the lifetime rules.
This patch still invokes UB (all accesses to the destroyed IdString instance are), but at least the optimiser
can't reason that destruct_guard_ok cannot be false and therefore it's safe to optimise out from its guard role.
The new bitwise case equality (`$bweqx`) and bitwise mux (`$bwmux`)
cells enable compact encoding and decoding of 3-valued logic signals
using multiple 2-valued signals.
These can be used to protect undefined flip-flop initialization values
from optimizations that are not sound for formal verification and can
help mapping all solver-provided values in witness traces for flows that
use different backends simultaneously.
- Attempt to lookup a derived module if it potentially contains a port
connection with elaboration ambiguities
- Mark the cell if module has not yet been derived
- This can be extended to implement automatic hierarchical port
connections in a future change
This code now takes the AST nodes of type AST_BIND and generates a
representation in the RTLIL for them.
This is a little tricky, because a binding of the form:
bind baz foo_t foo_i (.arg (1 + bar));
means "make an instance of foo_t called foo_i, instantiate it inside
baz and connect the port arg to the result of the expression 1+bar".
Of course, 1+bar needs a cell for the addition. Where should that cell
live?
With this patch, the Binding structure that represents the construct
is itself an AST::AstModule module. This lets us put the adder cell
inside it. We'll pull the contents out and plonk them into 'baz' when
we actually do the binding operation as part of the hierarchy pass.
Of course, we don't want RTLIL::Binding to contain an
AST::AstModule (since kernel code shouldn't depend on a frontend), so
we define RTLIL::Binding as an abstract base class and put the
AST-specific code into an AST::Binding subclass. This is analogous to
the AST::AstModule class.
There will soon be more (versioned) memory cells, so handle passes that
only care if a cell is memory-related by a simple helper call instead of
a hardcoded list.
Among other problems, this also fixes equality comparisons between
SigSpec by enforcing a canonical form.
Also fix another minor issue with possible non-canonical SigSpec.
Fixes#2623.
The only difference between "RTLIL" and "ILANG" is that the latter is
the text representation of the former, as opposed to the in-memory
graph representation. This distinction serves no purpose but confuses
people: it is not obvious that the ILANG backend writes RTLIL graphs.
Passes `write_ilang` and `read_ilang` are provided as aliases to
`write_rtlil` and `read_rtlil` for compatibility.
The new types include:
- FFs with async reset and enable (`$adffe`, `$_DFFE_[NP][NP][01][NP]_`)
- FFs with sync reset (`$sdff`, `$_SDFF_[NP][NP][01]_`)
- FFs with sync reset and enable, reset priority (`$sdffs`, `$_SDFFE_[NP][NP][01][NP]_`)
- FFs with sync reset and enable, enable priority (`$sdffce`, `$_SDFFCE_[NP][NP][01][NP]_`)
- FFs with async reset, set, and enable (`$dffsre`, `$_DFFSRE_[NP][NP][NP][NP]_`)
- latches with reset or set (`$adlatch`, `$_DLATCH_[NP][NP][01]_`)
The new FF types are not actually used anywhere yet (this is left
for future commits).
The $div and $mod cells use truncating division semantics (rounding
towards 0), as defined by e.g. Verilog. Another rounding mode, flooring
(rounding towards negative infinity), can be used in e.g. VHDL. The
new $divfloor cell provides this flooring division.
This commit also fixes the handling of $div in opt_expr, which was
previously optimized as if it was $divfloor.
The $div and $mod cells use truncating division semantics (rounding
towards 0), as defined by e.g. Verilog. Another rounding mode, flooring
(rounding towards negative infinity), can be used in e.g. VHDL. The
new $modfloor cell provides this flooring modulo (also known as "remainder"
in several languages, but this name is ambiguous).
This commit also fixes the handling of $mod in opt_expr, which was
previously optimized as if it was $modfloor.
As per suggestion made in https://github.com/YosysHQ/yosys/pull/1987, now:
RTLIL::wire holds an is_signed field.
This is exported in JSON backend
This is exported via dump_rtlil command
This is read in via ilang_parser
Krystine Sherwin
Miodrag Milanović
Martin Povišer
Emil J. Tywoniak
Philippe Sauter
Claire Xenia Wolf
N. Engelhardt
Roland Coeurjoly
Jannis Harder
Catherine
Rasmus Munk Larsen
Ethan Mahintorabi
Charlotte
dragonmux
Marcelina Kościelnicka
Henner Zeller
NotAFile
Lofty
Zachary Snow
Rupert Swarbrick
gatecat
Xiretza
clairexen
Vamsi K Vytla
Eddie Hung